INFO:
This driver works on Win 8 & 7 & Vista & XP, 32 and 64 bit and allows you to use Odin, ADB and Fastboot tools with your phone. There's a newer driver package around the net but they are INCOMPLETE, they lack essential drivers, so they may not work on all Samsung phones.
You can also download latest Odin, ADB & Fastboot Tools below.

WHAT'S THE HASSLE:
Samsung Drivers package's installation doesn't work on Windows 8 for many people (driver installation doesn't even start), so the point is that the drivers have to be installed manually. In order to do this I unpacked Samsung Drivers package .exe file so that the drivers can be installed via "have disk" method. I used these drivers succesfully in Windows 8 Enterprise x64 to connect my SGS i9000 to ODIN. Odin sees the phone and can flash firmware, reformat partitions etc.

INSTALLATION 1:
1. Download the driver INSTALLER.
2. Uninstall previous Samsung USB drivers from "Programs And Features" and "Device Manager".
3. Run the installer "USB_Drivers_1.5.29.0.exe" and proceed with the installation steps, finish the installation and restart your computer.
4. Connect it to your computer via USB cable.
5. If your phone is still not correctly recognized by Odin and the driver installer finished installation successfully - skip the 2nd method and use the 3rd. If drivers didn't install correctly (e.g. the installer failed to launch or failed to finish installation) - try the 2nd method first.

INSTALLATION 2:
1. Download the driver RAR ARCHIVE.
2. Uninstall previous Samsung USB drivers from "Programs And Features" and "Device Manager".
3. Unpack USB_Drivers_1.5.29.0.rar to some location, eg. C:\.
4. Run the installer from "C:\USB_Drivers\SAMSUNG_USB_Driver_for_Mobile_Phon es\setup.exe" and proceed with the installation steps, finish the installation and restart your computer.
5. Switch your Samsung phone into download mode (i9000: power it on with Power + Vol UP + Home pressed simultanously).
6. Connect it to your computer via USB cable.
7. If your phone is still not correctly recognized by Odin - try the 3rd method.

INSTALLATION 3:
0. This is the "have disk" method. You have to follow every step in this guide
1. Download the driver RAR ARCHIVE.
2. Uninstall previous Samsung USB drivers from "Programs And Features" and "Device Manager".
3. Unpack "USB_Drivers.rar to some location, eg. C:\.
4. Switch your Samsung phone into download mode (i9000: power it on with Power + Vol UP + Home pressed simultanously).
5. Connect it to your computer via USB cable.
6. Your phone should become discovered by Windows as some device. In my case, Windows has found my SGS i9000 as a "Gadget Serial" device.
7. Go to Windows Device Manager. Right click on the device your phone has been discovered as (eg. "Gadget Serial" in my case) and choose "Update driver" option from the context menu.
8. Choose "Search my Computer...", check "Include subfolders" option and point the updater to the folder where you've had unpacked the drivers .rar archive to, eg. C:\USB_Drivers.
9. The driver should install automatically.
10. It may happen that after the installation some new "unknown device" ("Samsung Modem" in my case) would appear in the Device Manager. Complete 7 & 8 step for that device and any other new device that may appear afterwards.
11. Restart your computer.
12. Done!

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